Conventional shuttleless looms have waste selvages that are cut off from the edge of the fabric just prior to the fabric being taken up on a take-up roller, and it is necessary to provide some way to remove the waste selvage after cutting. A conventional prior art arrangement is illustrated in FIG. 1 of U.S. Pat. No. 4,185,667.
Typically, waste selvage removal is accomplished by providing a pair of draw-off toothed wheels that mesh together tightly enough to pull the waste selvage between them, away from the loom, and into a waste selvage container. When lightweight yarns are being woven, the waste selvage often clings to the draw-off wheels, and becomes wound onto the wheels. Eventually this results in the waste selvage breaking, which allows it to wrap around the fabric take-up roller, or become intertwined with the fabric take-up mechanism. Substantial down time of the loom may result.
According to the present invention, the drawbacks inherent in the prior art are overcome in an extremely simple manner which does not require substantial modification of the loom, and which does not result in additional energy usage.
According to the present invention, apparatus for removing waste selvage containing warp ends interlaced with filling tails from a shuttleless loom is provided. The loom includes a suction source having an impeller pump with an exhaust, a fabric take-up roller, and a selvage trimming mechanism. The waste selvage removal apparatus according to the invention comprises a substantially downwardly directed venturi mounted below the fabric take-up roller in operative association with waste selvage trimmed from fabric being taken up by the fabric take-up roller.
An open-top waste selvage container is disposed below the venturi. Exhaust conduit means extend from the impeller pump exhaust to the venturi for providing the motive power for the venturi to suck waste selvage through the venturi and deposit it in the waste selvage container. The exhaust conduit means includes a pneumatic line connected to the pump exhaust and a branch connector connected to the pneumatic line, one branch leading to the waste selvage container, and the other receiving the waste selvage from between the draw-off wheels. A baffle means is provided at the branch for creating a rotary turbulence to twist waste selvage so that air won't blow the filling tails of the selvage out of the warpwise thread. Without the baffle means, that is the result. The motive force provided by the venturi, including the rotary turbulence induced by the baffle means, prevents the waste selvage--even when the yarn is light--from wrapping around the draw-off wheels.
A method of removing waste selvage containing warp ends interlaced with filling tails from a shuttleless loom is also provided according to the invention. The method comprises the steps of: Disposing the venturi so that it is substantially downwardly directed and below the axis of rotation of the fabric take-up roller, and in operative association with waste selvage containing warp ends interlaced with filling tails trimmed and integrally drawn, from the fabric. Connecting up the exhaust from the loom impeller pump so that exhausting air from the pump provides the motive force for the venturi. Operating the pump and the venturi so that air exhausting from the pump forms a vacuum passing through the venturi to draw the waste selvage downwardly from the fabric take-up roller; and inducing rotary turbulence at the venturi to effect twisting of the filling tail and warp end or leno yarns of the waste selvage together.
It is the primary object of the present invention to provide a procedure for simple and energy efficient waste selvage removal from a loom, and one that may be easily applied to existing looms. This and other objects of the invention will become clear from an inspection of the detailed description of the invention, and from the appended claims.